Duplicating machine



April 6, 1948. R w. BAlLEY ETAL 2,439,070

' DUPLICATING MACHINE Filed Feb. 6, i945 4 Sheets-heet 1 '6 a, INVENTORS.

W M -M 40342;?

.Al TTOKNEY- April 6, 1948.

R. w. BAILEY :r AL 2,439,070

, DUPLICATING MACHINE Filed Feb. 6, 1945 4 Sheets-Sheet? 47 A T RNEY.

April 194s. Rjw. BAl LEY HAL 2,439,070

DUPLICATING MACHINE Fiied Feb. 6, 1945. 4v Sheets-Sheet s IN V EN TORS.

.4 TTORNEy.

April 6, 1948. R. w. BAILEY EI'AL 2,439,070.

DUPLICATING MACHINE Filed Feb. 6, 1945 r 4 Sheets-Shee't 4 I INVENTORS. W 0. 64%, mum

.A r TORNEY.

Patented Apr. 6, 1948 DUPLICATIN G MACHINE Richard W. Bailey and Milo M. Harding, Los Angeles, Califl, assignors to Milo Harding 00., Los Angeles, Calif., a partnership Application February 6, 1945, Serial No. 576,455

13 Claims. 1

Our invention relates to means for copying written or printed matter, lines, letters or the compositions of them, and it has especial reference to a duplicating machine and to a paper feed mechanism therefor.

The chief object of the invention is to provide a simple feed means for a stencil duplicating device in which the paper is delivered to the duplicator drum and impression roller or platen, to be drawn therebetween Without the use of feed rollers or other feeding device that directly contact the surface of the paper to be printed, and in which no movement of the drum or platen or delivery device exists or occurs relative to the paper or other material to be printed, resulting in a friction that will in any way disturb the surface of said paper which consequently results in copies entirely free from paper lint that is common in the use of other feeding means.

A further object of the invention is to provide a simple means in which the paper is fed or delivered to the moving printing roller or drum and platen sothat the paper is speeded from a slow motion to a motion that is equal to the peripheral speed of the drum at the point of contact. So equalizing the speeds of travel of the paper and drum, there is no drag, and hence, no streaking or other marring of the paper, while insuring substantially accurate registration of each sheet, not possible by the commonly used feeding means.

Another object is to produce a means of feeding any weight of paper, whether thick or thin, without the necessity of making an adjustment of the feeding means.

Still a further object of the invention is to rovide a feed in a duplicating machine in which the sheet to be printed is positively gripped by prehensile means and positively moved forward while so gripped toward and between the duplidrum and its platen complement, without producing friction therebetween, said delivery device retaining the paper in positive control until the printing operation is completed.

Another object of the invention is to provide in a feed mechanism for duplicating machines, a means for releasing the paper while traveling at drum speed.

Gur invention also has for its objects to provide such means that are positive in operation, convenient in use, easily installed in a working position and easily disconnected therefrom, economical of manufacture, relatively simple, and of general superiority and serviceability.

The invention also comprises novel details, of construction and novel combinations and arrangements of parts, which will more fullyappear in the course of the following description. However, the drawings merely show and the following description merely describes one embodiment of the present invention, which is given by Fig. 5 is an enlarged fragmentary sectional de-.

tail on line 5-5 of Fig. 4, looking in the direction of the arrow.

Fig. 6 is a disassembled perspective view of the carriage assembly.

Fig. 7 is a perspective detail of one of the tie plates and'throat sections.

Fig. 8 is a fragmentary sectional elevational view, showing the forwardly moved positions of the carriage and paper.

Fig. 9 is an enlarged sectional detail, on line t-9 of Fig.8.

Fig. 10 is a sectional view taken on line lo-lil of Fig. 11.

Fig. 11 is an enlarged fragmentary section on lines I lll of Fig. 10, looking in the direction of the arrow.

Fig. 12 is a section taken on line Iii-I2 of Fig. 11.

Fig. 18 is a sectional detail taken on line i 3l 3 of Fig. 11.

Fig. 14 is an elevational detail of the cams for operating the carriage.

Fig. 15 is a fragmentary sectional elevation on line l5l5 of Fig. 14.

Fig. 16 is a side elevational view of Fig. 1, showing the cams and lever assemblies.

Fig. 17 is a fragmentary section on line l'l-l'l of Fig. 16.

Our invention includes the units and elements generally appurtenant to duplicating machines, as the drum and cooperating platen, and in a general sense, the important feed control for the paper, in which prehensile means are actuated to grip the paper and are then advanced to the drum and platen at a speed terminating in a climactic acceleration of the movement of the paper, which is equal to the peripheral speed of the drum and just prior to the prehension by the drum and platen of the paper. When the paper, traveling at the same rate of speed as the peripheral speed of the drum, contacts the drum and platen, then the prehensile gripping means are released and the paper thereby permitted to follow the contour of the drum and to be printed thereby.

Referring in detail to the drawings, the mimeograph frame is shown as comprising two side plates 2; suitably spaced apart and supporting a bed 3 for a stack of paper sheets 4 that are preferably held in aligned order by adjustable walls 5. In the side plates 2 is journaled a transverse V shaft 6, which mounts a plurality of friction rollers I, Figs. 1, 2, 3, 4 and 8, that are disposed in such relation to the forward end of a sheet of paper that they engage and move said sheet when revolved in the operation of the machine. These friction roller I, are desirably of rubber and are adjustably mounted on the shaft 6 for relative movement thereto and to one another to provide the necessary accommodation for differing widths of paper. Rotation of said shaft 6 is eifected through the cooperative medium of a rack 8 and pinion 9, this latter element being mounted on the one end of the shaft 6 with which it has an over-riding connection, Thus when the rack 8 is moved rearwardly or to the left in Figs. 1 and 16, the pinion 9 revolves freely on and independently of the shaft 6; but when the rack 8 is moved forwardly or to the right in said Figs. 1 and 16, the shaft is rotated and thus the paper, engaged by the friction rollers 1 on said shaft, is advanced or moved forwardly as hereinafter described. In order that, after a forward motion or travel of the paper for a definite extent, further travel be stopped through these rollers 1, the rollers l are removed from the zone of their contact with the paper and this is effected by elevating the shaft 6 thereby lifting the rollers l thereon from the paper. For this purpose the rack 8, which is slidably supported on a flanged wheel H, Figs. 16 and 17, that is journaled on a stud that extends from one of the side plates 2, is provided on the bottom with a thickened portion l2 connected with the thinner portion 8 by an incline l3, Fig. 16, the bottom of the rack, as seen in said Fig. 16, riding upon the flanged wheel H. Movement of the thinner portion 8 of the rack to the thicker portion [2 produces an elevation of the rack to a higher plane, and this upward movement of the rack carries with it the pinion 9 and the shaft 6, upon which are mounted the friction rollers 1. For this purpose, the shaft 6 is disposed in slotways I 4, in-

the side plates 2, in which it is vertically operable, the outside bearing 6' for the shaft being connected to arms l that are pivotally connected to the side plates 2. In this wise, the elevation of the shaft 6 and of the rollers thereon from the paper takes place in a positive manner, as does also the return of the roller 1 gravitationally, following the contour of the rack 8. The rack 8, as seen in Figs. 1 and 16, is pivotally connected at 16 to a lever ll, that is attached at one end to pivot on one of the side plates 2, and at the other end is provided with a roller l8, which is arranged to ride upon the periphery of a cam l9. By the revolution of this cam I9, the rack is reciprocated, in one direction that is to the left in Fig. 16, independently of the shaft 6, and in another direction, to-wit, to the right in said Fig. 16, to cause rotation of the pinion 9 and the shaft 6 and its friction rollers l, and an initial movement of the paper or a sheet of paper to the feed mechanism presently to be described, the amount of movement of the paper being a predetermined one. At the terminus of said movement of the paper, the shaft 6 and its rollers l are automatically lifted from contact with the paper, as the rack portion 12 rises onto and rides on the flanged wheel H when drawn during the revolutionary movement of the cam [9. The continued revolution of the substantially concentric portion of the cam 19 holds the rack 8 inactive until another sheet is ready to be delivered in the manner stated.

The cam I9 is integral with a sleeve 20 that is pinned or otherwise secured to the reduced end of a journal 2|, which extends through the side plates 2 and beyond one of them, and operates in bearings 22. The journal 2| mounts a printingdrum 23, and the end of the journal 2| is provided with means for rotating same, in this instance, a crank 24, Fig. 1, though it is obvious that any other prime mover may be employed. In cooperation with the printing drum 23 is a platen 2-5, that is journaled in bearings 26 in the ends of arms 21 secured to the side plates 2 and adjustable to provide for cooperative engagement thereof with the printing element 23 to hold a sheet of paper in contact with the printing element to receive the impression thereof. It is believed clear, without any further illustration, that the platen serves only to hold the paper against thev printing drum during the printing revolution thereof and that upon ejection or passage of the paper, the platen is removed from contact with the printing drum, as otherwise it would receive the ink therefrom and besmear succeeding sheets. Since the means for accomplishing this removal from the printing drum forms no part of the present invention, it is not further referred to, nor illustrated nor described.

Between and binding together the side plates 2, is a pair of transverse members 28 and 29, relatively superposed and spaced to, provide a throat, guide and support for a sheet of paper. The member 28 is formed with a vertical portion 30, having bent ends M, which fit against and are secured to the side plates 2, and which journal a transverse rod or bar 32 that is provided with a series of spaced, flat springs 33. These springs extend through openings 34 in the horizontal planar area 35 of the transverse member 28 and exert a slight pressure against the face of the sheet of paper and maintain it under a feeble tension, sufiicient only to keep it flat and free of wrinkles. The member 28 is also formed with a horizontal planar area or surface 35'that is provided with a plurality of parallelly arranged slots 35, between which are disposed the aforenamed openings 34. The cooperating member 29 is formed of a vertical plate 31 and a horizontal plate 38, Fig. '7, that is parallel to the horizontal planar area 35 of the member 23. The-horizontal portion of the member 29 is provided with slots or cut-out portions 39 which register with the slots 36 in the planar area of the member 28, the slots being provided for purposes presently appearing. The member 29 connects the two side lates 2, and the upstanding or vertical portion 30 of the member 28 also'connects the two side portions, but the edges of the horizontal portion or planar area 35 are free of the side plates 2, as are also the edges of the horizontal plate 38 of the member 29. These plates 35 and 38 are supported in their spaced relation by hangers 40, the spacing of these plates being provided for the purboss of permitting travel to "and fro or complements of a carriage 4|. The carriage 41 comprises a body, the ends 42 of which are bentforwardly and formed with substantially horizontal times 43, projecting therefrom, and depend ing extensions 44. The conjoining portion of thebody, that the strip or section '45, connecting the ends 42 and the projecting tangs 43, is, as seen in the various figures, bent in am gularwise to reinforce same. The tangs 43 are provided with journaled rollers 46 which are flanged as at 41. These rollers 45 operate in ways 48 in the side walls 2 and are retained in said ways by the "flanges 47,,whicl1are on the,

outside of the side walls 2; The carriage '4! is provided with a transverse strip, .bar or flat plate 49, that serves as a thrust bar, which as seen in Figs. 2, 8, '10 and 11, extends between the transverse members 28 and 29, thatare spaced, as heretofore described, to provide la. throat for the reception of the paper sheet and a uide therefor. Cooperating with the strip or bar 49, is a plurality of gripping members :or elements, which in the present instance, comprise preferably rubberblocks or bodies 50., which are adapted to be operated in any desirable manner to grip the sheet of paper A. For. this purpose, the

rubber block or bodies 5t are mounted in spaced relation in a square tube 5|, Fig. 6, which at its respective ends is provided with substantially vertical grooves 52, Figs. 6, 11 and 13, coacting with vertical tongues 53 on theinside f the depending extensions 44 to maintain the gripper tube in position during its vertically sliding movement, which is effected positively in an upward direction to cause the rubber or other friction bodies 50 togrip a sheet of paper by pressing it into contact with the thrustbar 49, by a rod or other member 54. This member 54 is trunnioned in the said-depending extensions 44, of the carriage 4i, vand is provided with an inclined arm 55 havin anaxle 56 on which is rotatably mounted a roller 51. The rod 54 is flattened, as at 54', on its upper side andnormally lies flush with or parallel to, the underside of the square tube 5!, as seen in Fig. 1i). Upward movement of the tube 5|, iseffected by a partial rotation or axial movement of said rod 54, which also maintains said tube 5! in its position for gripping the paper A, and this axial rotation of the rod 54 is accomplished by a substantially parallelogramma-tic unit 58, upon the horizontal rail 59 of which rides the roller 51. The component members fill and 61 of the unit 58 are pivotally connected at their upper ends to the respective ends of the horizontal rail, and at their lower or bottom ends are mounted for pivoting movement in one of the side walls 2. The members 60 and 6! are held in and -operated to the necessary angle of inclination for controlling the level of the rail 59, by a cam 62, which bears against an edge of the member 68, such contact being insured by a spring 63. The

cam 62 is mounted for oscillation on a shaft 64,

extending through a bearing 55, assembledin a wall 2 of the frame, the bearing 65, which is in the nature of a sleeve, housing and being pinned to that portion of the shaft 64 which projects beyond the wall 2. The sleeve or bearing 55 is integral with a lever 66, Figs. 11 and 16, thatat its upper end is provided with a roller 67, which rides upon the periphery of a cam 58, secured to the aforenamed sleeve 20. Engagement of the roller 6! on the lever 66 is insured by a spring 69' which connects the lower end of said lever the members 28 and 29.

with the lower end of the aforenamed lever l1. Revolution of the cam 68, following a sequence of actions hereinafter described, produces an arcuate swing of the cam 62, through the lever 66, such arcuate motion being exerted against the member 69 of the parallelogram unit 58, which is thereby elevated, thereby causing the horizontal rail 5% to rise to a position substantially as indicated in Fig. 10, from a dotted line position to the full line position, which is the limit of its upward movement. Such movement causes the arm to move the rod 54 axially to he position substantially as illustrated. in Figs.

.350 and 12,. in which, it will be seen, that the flattened surface 54', in assuming an angular relation to the'planar underside of the square tube Si, by reason of the elevation of the parallelogram rail 59, lifts said square tube 5| and causes the friction bodies to engage, press and hold a sheet of paper against the thrust plate 49 of the carriage 4!. The grip or hold Of these friction bodies continues so long as the parallelogram unit .58 is held elevated and during the entire traverse of the roller 51 over the rail 59, which is controlled entirely by the cam E8. The upward movement of the square or angular bar 51 and its gripping rubber units 58 occurs relatively to the plate or member 29, which'combines with its associate plate .28 to form the aforedescribed throat for the reception of the paper. Such movement of the bar 51, causes the rubber blocks or bodies to pass through the slots or elongate openings 39 in. the horizontal part 38 of the member 29 and to press the paper against the thrust bar 49 of the carriages 4!, thereby to grip it and to hold it gripped during the forward movement of the carriage to deliver the sheet of paper to theprinting drum or element 23. It will be observed that the openings or cut-outs in the member .29 are elongate in a longitudinal direction and that the rubber bodies at when extended therethrough by the operation of said angle bar 5|, travel in said cut-outs with the carriage 4i, and relative to The reciprocation 0f the carriage 4| in one direction to move the paper forward, and in another direction to "return it to initial position preparatory to gripping a new sheet for a repetition of the cycle, is effected by a cam 69 coupled with a follower cam Iii, both cams being integrally associated with the sleeve 20, heretofore described in connection with the axle of the printing drum 23. Two rollers H and T2, respectively engage the pe'ripheriesrof said cams 59 and 15!. The rollers H and F2 are mounted in the ends of tin-es of a bifurcated lever 13, that is mounted to pivot on one of the side plates 2, theroller Htraversing the periphery of the cam 59. and the roller 12 traversing the periphery of the cam 18 and following thetracking motion of the roller 1-]. The tines oi the lever it, for the purpose of permitting the simultaneous engagement of the two earns; 69 and ill, are ofise't with respect to each other, as viewed in Fig. 1. Qneof the .tangs 43 of the carriage is connected to the produce a complete cycle of operations during each complete revolution of the cams GS and Ill, and of the other cams l9 and 6B.

As stated heretofore, the initial movement of a sheet of paper by the rollers I, carries the paper into and through a part of the throat between the members 28 and 29. This travel of the paper is a limited one, controlled by the cam l9 and the rack 8 and pinion 9, the limit being imposed by the necessity of gauging the subsequent distance of passage of the paper to the printing element 23. Since the travel of the carriage 41 is a predetermined one, the location of the paper on the carriage must be so related that when the carriage advances with the paper gripped, the paper will be delivered to between the printing drum 23 and its complementary platen 25, while still gripped and at drum speed. The location of the paper is governed by normally upturned stop members 15, formed on the ends of spaced fingers 16, provided on a plate ii, that is fixed to a transverse flattened shaft i8, Fig. 6, journaled in the depending extensions 44, of the carriage ll. The underside of the plate I! is provided with a swiveling connection 38, Fig. 9, for a post 19 receiving and extending within an end of a helical compression spring 80, the other end of which is extended over and seated on the shoulder of a companion post 8| that is pivotally attached to the vertical wall 3'! of the member 29 and is separated from the post 19. The compressive action of the spring 80 holds the plate '11 against the underside of the horizontal section 38 of the member 29, and the stop members 15 of the fingers project through the elongate slots 39 therein, when the carriage is in normally retracted position, as seen in Fig. 2, in which position it remains during the stripping action of the rollers I, which delivers a sheet of paper from a stack to contact with the stop members 15.

Assuming that the revolution of the drum 23 and the various cams appurtenant thereto is continuous, the cam 68 will, through its described connections, operate the cam 62, which in turn will press against the member Bl] of the parallelogram unit58 and elevate the rail complement 59 thereof. Such elevation causes the arm 55 to tilt the bar 54, and thereby to lift the square tube 5|, with friction bodies 50, which are thus caused to press the paper against the thrust bar 49 of the carriage and to grip the same. The action of the gripping means 56 occurs after the friction rollers I have moved the sheet of paper between the members 28 and 29 to and in contact with the stop 15 and it will be noted that the gripping of the paper takes place rearwardly of the forward or front end of the paper and at a distance therefrom which is equal or substantially equal to the distance of travel of the carriage 4| toward the printing element whereby the edge of the paper, guided by and between the members 28 and 29, is presented to the printing element 23. The grip- Der means close on the paper after the feed rollers l have moved the paper to and in engagement with the stop; and following the gripping action, the initial feed rollers are lifted from the paper as the cam is draws the cam portion of the rack 8 over the roller I3, as described. Thereupon, through the medium of the cams 69 and 10, the carriage begins its forward motion, with the paper gripped and connected thereto. Simultaneously, the stop plate H with its stop fingers 16, extended through the cutout or openings 39, moves downwardly, the spring 8|], anchored on the rigid vertical wall 31 of the member 29, causing the stop plate to pivot in its bearing in the moving carriage M and as the carriage reaches the extremity of its movement. to assume the position substantially as shown in Figs. 8 and 10. The edge of the paper, at the end of the forward movement of the carriage, which undergoes an acceleration through the cam 69 and HI to cause the paper to travel at a speed equal to the peripheral speed of the printing drum, is in contact with the drum and the platen 25, to which the paper is released by the release of gripper bodies 50. The carriage 4!, with the gripper means open, returns to initial position, preparatory to a repetition of the cycle of movements, and during such return movement, the stop plate 11 is gradually caused to return to its normal position under the compressive action of the spring 80. The cams 69 and ill, as explained, are so formed that the steady advance. or forward movement of the carriage 4! is climaxed by an accelerated movement which is equal to the peripheral speed of the printing drum. In this wise, there is no force exerted by the printing element to draw the paper and hence clean copy and perfect registration are obtainable.

It will be understood that the gripper bodies are released suddenly at the end of the forward movement of the carriage, as the arm 55 slides off the rail 59 and onto the inclined member 60, and remain inactive during their return to starting position. For this purpose, the rail of the parallelogram unit 58 is caused to drop through the action of the cam 68, whereby the arm 55 and its connections, following such descent, permit the angular tube 5| to drop and thereby to hold the friction bodies 59 removed from the area of passage of a new sheet of paper.

While we have illustrated and described what we now regard as the preferred embodiment of our invention, the construction is, of course, subject to modifications without departing from the spirit and scope of our invention. We, therefore, do not wish to restrict ourselves to the particular form of construction illustrated and described, but desire to avail ourselves of all modifications that may fall within the scope of the appended claims.

Having thus described our invention, what we claim and desire to secure by Letters Patent is:

1. In a duplicating machine having a printing element, a fixed paper guide, a movable stop means for the end of a sheet of paper associated with said guide, an initial moving means to move the end of the paper in contact with said stop means, a carriage operable relative to said guide :means, a thrust member on said carriage and above the paper in said guide, means to press the paper rearwardly of the end thereof in engagement with said thrust member to connect the paper with said carriage, means separate from and beneath said carriageto operate said pressing means, means to move said carriage relative to said guide, means operable during said movement tomove said stop means out of the path of said paper and to deliver theend of the sameto the printing element, cam means to control all of said means in the order named and including. cam means for moving the carriage at an accelerated speed until the same equals the peripheral speed of the printing element, whereby the paper simultaneously is connected. to the carriage and in operative engagement with the printing element.

2. In a duplicating machine, a rotary printing element, a platen cooperating therewith, retractable stop means, a reciprocable carriage movable 9 to convey a sheet of paper disposed against the stop means to a position in which the sheet of paper is fed between the rotary element and the platen, bar means on the carriage arranged to extend transversely of the sheet of paper and above the same, the bar presenting a flat surface to the paper and engaging the upper face thereof at the sideportions that are beyond the portions to be printedand in between such. portions, gripping means on the carriage arranged to engage the under side of the sheet of paper and clamp same against the flat surfaced bar, a stationary member beneath the carriage, a connection between the latter member and the stop means and operative to remove said stop means prior to the movement of the carriage to its position nearest to the rotary element, and cam-controlled mechanism connected to reciprocate the carriage and rotate the printing element synchronously.

3. In combination, a printing drum and platen, drive means for rotating said drum to feed a sheet continuously between it and the platen, roilermeans controlled by the drive-means for moving a sheet toward the drum, stop means for said sheet forward of the platen, normally open means to gri p an intermediate part of said sheet after the same has been stopped, means controlled by the drive means to retract the stop means and simultaneously move the sheet gripping means toward the platen to be gripped between the latter and the drum and at an accelerating speed until said speed equals the peripheral speed of the drum means to release the sheet gripping means during the latter movement thereof, and means to return the sheet gripping means to its normal, initial open condition and simultaneously restoring the stop means to sheet stopping position.

4. In combination, a printing drum and a platen, drive means for rotating said drum to feed a sheet continuously between it and the platen, roller means controlled by the drive means for moving a sheet toward the drum, stop means for said sheet forward of the platen, normally open means to grip: an intermediate part of said sheet after the same has been stopped, means controlled by the drive means to retract the stop means and simultaneously move the sheet gripping means toward the platen to be gripped between the latter and the drum at an accelerating speed until said speed equals the peripheral speed of the drum means to release the sheet gripping means during the latter movement thereof, and means to return the sheet gripping means to its normal, initial open condition and simultaneously restoring the stop means to sheet stopping position, said drive means including a cam for controlling the movement of the roller means, a cam controlling the movement, of the gripping means toward and from the platen, and cam-actuated means for operating the gripping means.

5. In combination, a printing drum and a platen, drive means for rotating said drum to feed a sheet continuously between it and the platen, roller means controlled by the drive means for moving a sheet toward the drum, stop means for said sheet forward of the platen, normally open means to grip an intermediate part of said sheet after the same has been stopped, a common carriage mounting both the gripping and the stop means, calm means controlled by the rive means for reciprocating said carriage to-- ward and from the platen, said cam means being so formed that the movement of the carriage toward the platen accelerates until the speed thereof equals theperi pheral speed of the drum, means, during said latter movement, for retractins the stop means, means, operable after the sheet is gripped between the drum and platen, to release the ripping means, nd means to return, the carriageto its initial position and simultaneouslyiestore the stop means to sheet stopping position.

6. In combination, a printing drum and a platen; drive means for rotating said drum to feed a sheet continuously between it and the platen, roller means controlled by the drive means for moving a sheet toward the drum, stop means for said sheet forward of the platen, normally open means to grip an intermediate part of said sheet. after the same has been stopped, a com-- mon carriage. mounting both the gripping and the stop means, cam means controlled by the drive means for reciprocating said carriage toward and from the platen, said cam means. being so formedthat the movement. of the carriage toward the platen accelerates until the speed thereof equals the peripheralspeed or" the drum, means, during said latter movement, for retracting the stop means, means, operable after the sheet is gripped between the drum and platen, to release the gripping means, and means to return the carriage to. its initial position and simultaneously restore the stop means to sheet stopping position, said drive means including a calmior controlling the movement of the roller means, a cam for controlling operation of the sheet gripping means, and cam means 'for controlling the movement of the carriage.

7. In combination, a printing drum and a platen, drive means for rotating said drum to feed a sheet continuously between it and the platen, roller means controlled by the drive means for moving a sheet toward the drum, stop means for said sheet forward of the platen, normally open means to grip an intermediate part of said sheet after the same has been stopped, a common carriage mounting both the gripping and the stop means, calm means controlled by the drive means for reciprocating said carriage toward and from the platen, said cam means being so formed that the movement of the'cai'riage toward the platen accelerates until the speed thereof equals the peripheral speed of the drum, means, during said latter movement, for retracting the stop means, means, operable after the sheet is gripped between the drum and platen, to release the gripping means, and means to return the carriage to its initial position and simultaneously restore the stop means to sheet stoppling position, said drive means including a cam for controlling the movement of the roller means, a cam. for controlling operation of the sheet gripping means, and cam means for controlling the movement of the carriage, all of said cams and cam means being fixed with respect to. each other and movable together bodily.

8. A paper feeding mechanism for duplicating machines having a movable printing element mounted between a pair of support members, a carriage between said members having end portions within and adjacent said members and a transverse Wall connecting the portions, means on said end portions having movable connection with the support members, paper gripping means comprising said transverse wall and a grip member movable in relation thereto, means to move the carriage, the gripping means and paper 11 gripped thereby in a direction toward the printing element to bring said paper into operative engagement with said element, said means comprising cam-controlled mechanism for moving the carriage first at a speed less than the speed of movement of the printing element and then at the same speed, and means to open the gripping means to release the paper so gripped and moved subsequent to said operative engagement.

9. A paper feeding mechanism for duplicating machines having a movable printing element mounted between a pair of support members, a carriage between said members having end portions within and adjacent said members and a transverse wall connecting the portions, means on said end portions having movable connection with the support members, paper gripping means comprising said transverse wall and a grip member movable in relation thereto, retractable stop means on the carriage and normally disposed in the path of the paper to stop the same, means to move the carriage, the gripping means, the paper and the stop means in a direction toward the printing element to first retract the stop means and then bring said paper into operative engagement with said element, said means comprising cam-controlled mechanism for moving the carriage first at a speed less than the speed of movement of the printing element and then at the same speed, and means to open the gripping means to release the paper so gripped and moved subsequent to said operative engagement.

10. In a duplicating machine having a rotary printing drum mounted on an axle and adapted to be continuously rotated on said axle, a bank of cams fixed to rotate with the drum, roller means for feeding successive sheets of paper from a stack thereof toward the drum, a gear rack, an operative connection between the latter and one of said bank of cams for reciprocating said rack, a gear pinion on the roller means and engaged .with the rack, said pinion being connected to said roller means to drive the latter in one direction of rotation only, and means for elevating the rack, pinion and roller means simultaneously to raise said roller means out of feeding engagement with the sheets of paper when the rack is moved by the mentioned cam to its end feeding position.

11. In a duplicating machine having a rotary printing drum mounted on an axle and adapted to be continuously rotated on said axle, a bank of cams fixed to rotate with the drum, roller means for feeding successive sheets of paper from a stack thereof toward the drum, a carriage including stop means for said paper to limit the movement imparted by the roller means and gripping means for the paper, an operative connection between the carriage and one of said bank of cams for moving the carriage toward the drum first at a speed less than the peripheral speed of-the rotary printing drum and then at an equal speed whereby the paper gripped by the carriage is brought into operative engagement with the drum while the same is so gripped,

and means for subsequently releasing the paper.

gripping means.

12. In a duplicating machine having a rotary printing drum mounted on an axle and adapted to be continuously rotated on said axle, a bank of cams fixed to rotate with the drum, roller means for feeding successive sheets of paper from a stack thereof toward the drum, a carriage including stop means for said paper to limit the movement imparted by the roller means and gripping means for the paper, an operative connection between the carriage and one of said bank of cams for moving the carriage toward the drum first at a speed less than the peripheral speed of the rotary printing drum and then at 13. In a duplicating machine having a rotary printing drum mounted on an axle and adapted to be continuously rotated on said axle, a bank of cams fixed to rotate with the drum, roller means for feeding successive sheets of paper from a stack thereof toward the drum, a carriage including stop means for said paper to limit the movement imparted by the roller means and gripping means for the paper, an operative connection between the carriage and'one of said bank of cams for moving the carriage toward the drum first at a speed less than the peripheral speed of the rotary printing drum and then at an equal speed whereby the (paper gripped by the carriage is brought into operative engagement with the drum while the same is so gripped,

and means for subsequently releasing the paper gripping means, said stop means comprising a retractable member and means having a fixed end connection and connected to said member to retract the latter upon the mentioned movement of the carriage.

RICHARD W. BAILEY. MILO M. HARDING.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 705,181 White July 22, 1992 929,293 Dick July 27, 1909 1,131,836 Heywood et al Mar. 16, 1915 1,516,228 Brasseur Nov. 18, 1924' 1,595,208 Marquardt Aug. 10, 1926.; 1,741,848 Kelly Dec. 31, 1929 1,876,255 Marquardt Sept. 6, 1932 2,275,455 Neal Mar. 10, 1942 2,276,297 Flood Mar. 17, 1942 2,376,255 Hunting May 15, 1945 

